Currently, a number of consumer electronic devices are adapted to receive speech from a near-end talker (or environment) via microphone ports, transmit this signal to a far-end device, and concurrently output audio signals, including a far-end talker, that are received from a far-end device. While the typical example is a portable telecommunications device (mobile telephone), with the advent of Voice over IP (VoIP), desktop computers, laptop computers and tablet computers may also be used to perform voice communications.
In these full-duplex communication devices, where both parties can communicate to the other simultaneously, the downlink signal that is output from the loudspeaker may be captured/acquired by the microphone and get fed back to the far-end device as echo. This is due to the natural coupling between the microphone and loudspeaker, e.g. the coupling is inherent due to the proximity of the microphones to the loudspeakers in these devices, the use of loud playback levels in the loudspeaker, and the sensitive microphones in these devices. This echo, which can occur concurrently with the desired near-end speech, often renders the user's speech difficult to understand, and even unintelligible over a course of such feedback loops through multiple near-end/far-end playback and acquisition cycles. Echo, thus, degrades the quality of the voice communication.